The present paper describes a new process for designing and applying selected passive heating and cooling techniques in a large urban area of Legnano, a city close to Milan. The planning restoration process is based on the integration of several natural and man-made factors with the bio-climatic criteria of individual buildings' design. The architectural rehabilitation of two historical industrial buildings, selected as representative in the overall urban renewal of the considered Cantoni urban area, has been considered as an integral part of the whole urban planning process. The buildings' design is further developed using solar passive heating/cooling techniques such as the insertion of an atrium between the buildings and the placement of green roofs on the building's bare coverings. The thermal behaviour of one of the above mentioned buildings equipped by passive heating and cooling techniques is calculated and analysed in the present paper using a transient building's performance simulation program. (C) 2001 Elsevier Science Ltd. All rights reserved.